JP3425629B2 - Wheel cooling method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal core and a metal core.
The present invention relates to a whetstone cooling method for cooling a whetstone made of a whetstone layer provided on an outer periphery of a whetstone with a coolant. 2. Description of the Related Art Generally, in a grinding machine, a grinding wheel is brought close to a workpiece while rotating the grinding wheel and the workpiece together, thereby performing cylindrical grinding of the workpiece, or contacting the grinding wheel while rotating the grinding wheel. The truing of the grindstone is performed by detecting the contact of the grindstone by approaching the detection pin, or by causing the grindstone to approach the rotary truer while rotating the grindstone and the rotary truer together. [0003] The diameter of a grinding wheel is measured by bringing the grinding wheel into contact with a contact detection pin, and the amount of movement of the grinding wheel with respect to the rotary truer is calculated based on the diameter of the grinding wheel. In this case, the grinding stone is trued by a predetermined amount. [0004] The above-mentioned grindstone comprises a disk-shaped metal core made of iron and a grindstone layer provided on the outer periphery of the metal core. When contact is detected, no coolant is applied to the grindstone. When the grindstone is rotated at a high peripheral speed, the metal core thermally expands due to frictional heat between the metal core and air, and the grindstone diameter increases. Conversely, during truing, the coolant is applied to the grindstone, so that the temperature of the metal core decreases and the grindstone diameter decreases. As a result, there has been a problem that accurate truing of the grindstone cannot be performed due to a change in the grindstone diameter. [0005] The present invention SUMMARY OF] has been made to solve the problems described above, the abrasive consisting of a disc-shaped metal core and the grindstone layer provided on the outer periphery of the metal core
When truing the grindstone layer with the stone rotated
Cooling the metal core by discharging coolant to the side of the metal core
Before truing, the surface of the grindstone layer and the contact detection
When detecting the contact position by contacting the
A metal core by discharging coolant to the side of
By cooling, under the same cooling conditions as truing
The grinding wheel is cooled so as to detect the contact position . When the coolant is applied to the side of the metal core near the rotation center of the grindstone while rotating the grindstone, the coolant is diffused in the radial direction by the rotational centrifugal force of the grindstone to cool all the side faces of the metal core. . As a result, thermal expansion of the grindstone due to friction of air can be prevented. An embodiment of the present invention will be described below with reference to FIG. Reference numeral 10 denotes a bed.
1 is mounted movably in the left-right direction. Table 1
1, a headstock 12 and a tailstock 13 are installed to face each other, and a workpiece W is supported at the center by the headstock 12 and the tailstock 13. The headstock 12 has a workpiece rotating motor 14 for rotating and driving the workpiece W, a truing device 15 for truing the grindstone, and a contact detecting device 16 for detecting the contact of the grindstone.
Is installed. The bed 10 has the table 1
A servomotor 17 for moving the motor 1 through a ball screw mechanism (not shown) is attached. A bed 10 is mounted on the bed 10 so as to be movable in the front-rear direction.
Is supported rotatably about an axis parallel to the moving direction of the table 11. A grindstone drive motor 22 that rotationally drives a grindstone 21 and a grindstone 2
A coolant supply device 23 that supplies coolant to a grinding point between the workpiece 1 and the workpiece W, and a grindstone cover 24 that covers most of the grindstone 21 are attached. The grindstone 21 is provided on the grindstone cover 24.
Is mounted. The bed 10 is provided with a servomotor 26 for moving the grindstone table 20 via a ball screw mechanism (not shown). The servomotor 26 is provided with an encoder 27 for detecting the position of the grindstone table 20. As shown in FIG. 2, the truing device 15 is attached to the side surface of the headstock 12 on the side of the grinding wheel head 20, and the truing device 15 is a rotary truer 30.
And a truer drive motor 31 for rotating the rotary truer 30 about an axis parallel to the rotational axis of the grindstone 21. As shown in FIG. 2, the contact detection device 16 includes a bracket 32 on a side surface of the headstock 12 on the side of the grinding wheel head 20.
The contact detection device 16 includes a contact detection pin 33 and an AE sensor 34 fixed to the contact detection pin 33. As shown in FIGS. 2 and 3, the grinding wheel 21 comprises a disk-shaped metal core 35 made of iron and a grinding layer 36 fixed to the outer periphery of the metal core 35.
5 is fixed by a bolt 37 so as to be sandwiched between a grindstone shaft 38 and a movable flange 39 made of metal.
The grindstone cooling device 25 has a first pipe 40 fixed to the grindstone cover 24 so as to face the movable flange 39 on the rotation axis of the grindstone 21, and the first pipe 40 is provided with a pressure reducing valve 50.
And a tank 53 via an electromagnetic directional switching valve 51 and a pump 52.
The coolant in the tank 53 is controlled to a constant temperature by the heater 54 and the cooler 55. As shown in FIGS. 1 and 3, the coolant supply device 23 has a coolant nozzle 60 attached to the grindstone table 20, and the coolant nozzle 60 is connected to the first pipe 40 via the second pipe 61. Similarly, it is connected to the tank 53 via an unillustrated pressure reducing valve, electromagnetic directional switching valve, and pump. In FIG. 1, reference numeral 70 denotes a central processing unit, to which servo motors 17 and 26 are connected via drive circuits 71 and 72.
0 is the memory 73, the AE sensor 34 and the encoder 2
7 is connected. Next, the operation will be described based on the above configuration. Each time a plurality of workpieces W are ground, contact detection of the grindstone 21 and truing of the grindstone 21 are continuously performed. When grinding the workpiece W, the coolant is supplied from the coolant nozzle 60 and the coolant is supplied from the first pipe 40. Further, the grindstone 21 and the workpiece W are rotated, and the grindstone table 20 is rotated.
And the table 11 are sent by NC. When detecting contact with the grindstone 21, the coolant from the coolant nozzle 60 is stopped, and the coolant is discharged from the first pipe 40. Further, the grindstone 21 is rotated, and the grindstone table 20 is moved forward. When the contact detection pin 33 comes into contact with the grindstone 21, a contact signal is output from the AE sensor 34 to stop the advance of the grindstone table 20 and to take the output of the encoder 27 into the memory 73 via the central processing unit 70.
Based on the output of the encoder 27, the current grindstone diameter and the position of the tip of the grindstone are calculated, and the grindstone table 20 is retracted. Since the coolant is not caused to flow from the coolant nozzle 60, the contact can be detected accurately. When the grinding wheel 21 is to be trued, the coolant from the coolant nozzle 60 is caused to flow and the first
The coolant is discharged from the pipe 40, and the grindstone 21 and the rotary truer 30 are rotated together. Further, the feed amount of the grindstone base 20 is calculated based on the position of the tip of the grindstone calculated earlier, the grindstone base 20 is advanced toward the rotary truer 30 by the calculated feed amount, and the width of the table 11 is set to the width of the grindstone 21. Move by minutes. When the truing is completed, the wheel head 20 is moved backward. As described above, when grinding, contact detection, and truing, that is, when the grindstone 21 is rotating, the first
Coolant is applied to the side of the movable flange 39 from the pipe 40, and the coolant is applied to the metal core 3 by the rotational centrifugal force of the grindstone.
5 moves (diffuses) in the radial direction of the grindstone 21 while being transmitted to the side surface of the metal core 35, so that the metal core 35 is cooled,
It is possible to prevent the grinding wheel 21 from thermally expanding due to frictional heat between the grinding wheel 21 and air. Therefore, the change in the grindstone diameter is reduced, the truing amount of the grindstone 21 becomes accurate, and the processing accuracy is improved. In the above-described embodiment, the first pipe 40 is provided on the movable flange 39 side.
The pipe 40 may be provided not only on the movable flange 39 side but also on the grindstone table 20 side as shown by a broken line B, and coolant may be applied from both side surfaces of the grindstone 21. In the above-described embodiment, the coolant is directly applied to the side surface of the movable flange 39, and the coolant flowing in the radial direction by centrifugal force is
The side surface of the metal core 35 is set so as to be close to the rotation center of the grindstone 21.
The pipe 40 may be provided, and the coolant may be directly applied to a portion near the rotation center of the grindstone 21 in which the side surface of the metal core 35 is exposed. As described above, according to the present invention, while rotating the grindstone, the coolant is applied to the side of the metal core close to the rotation center of the grindstone. Is cooled, the thermal expansion of the grindstone due to frictional heat between the metal core and the air can be prevented, and the effect of suppressing the change in the grindstone diameter can be obtained.

[Brief description of the drawings] FIG. 1 is an overall plan view of a cylindrical grinding machine according to the present invention. FIG. 2 is a partially enlarged sectional view of FIG. FIG. 3 is a view taken in the direction of arrow A in FIG. 2; [Explanation of symbols] 16 Contact detection device 20 Wheel head 21 Whetstone 24 Whetstone cover 25 Wheel cooling device 35 metal core 36 grinding stone layer 40 1st piping 50 pressure reducing valve 51 Solenoid directional switching valve 52 pump 53 tank

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Akimitsu Kamiya 1-1-1 Asahimachi, Kariya City, Aichi Prefecture Inside Toyota Koki Co., Ltd. (56) References JP-A-59-88260 (JP, A) Japanese Utility Model Showa-56 −89457 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B24B 55/02 B24B 53/04 B24B 53/08

Claims (1)

(57) [Claims 1] A state in which a grindstone composed of a disk-shaped metal core and a grindstone layer provided on the outer periphery of the metal core is rotated.
In truing the whetstone layer, the metal core
Cooling the metal core by discharging coolant to the side,
Before the truing, the surface of the grinding wheel layer and the contact detecting member
When detecting the contact position by contacting the
Discharging the coolant to the side surface of the metal core
By further cooling the metal core, the true
To detect the contact position under the same cooling conditions as
A method for cooling a grinding wheel, comprising cooling the grinding wheel.